The newest CD/DVD by Celtic Thunder doesn't have Irish music, I admit, but if you look into their previous ones, there is a lot more.
You should look at Raggle Taggle Gypsey (there is a great part with a Bodhrán, a traditional Irish drum, plus it is an old Irish/Celtic song!) or Danny Boy or Homes of Donegal.
I really do encourage you to look in to more of their music, it really is good.
mg: you're right, the young one(Damian McGinty) is VERY talented. All of them are. I suppose Celtic Woman can be a bit much at times. :)
As for Celtic Thunder, they are better live because they have more personality.

By the way: since you all seem to be into Celtic music, have you listened to Gaelic Storm, Cherish The Ladies, Mick Moloney?
Any recomendations for other good Irish music?

Kay